SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55e2553f1edb30fdf49efdf9b448229b785e2693eccb31820885fcdf6d529b7e' 
  AND token = 'S7HFh98f6/Ul+vxgLeTkxOskARFuQIk2QapdagTL3X0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}